Adjustable retainer for a headrest

ABSTRACT

A chair back supports a positionable headrest assembly including a post and headrest with the post manually positionable in a channel on the chair back. A retainer arm bears against the post to inhibit post travel against all but deliberately applied force, as for example, by a dental assistant when adjusting a dental chair to accommodate the next patient. A threaded member in the chair back is settable to apply the desired resistance to post travel during headrest adjustment. Access to the threaded member for adjustment purposes may be by an opening in the chair back normally receiving a fastener securing a chair component.

BACKGROUND OF THE INVENTION

The present invention concerns adjustable headrests as found on dentalchairs, vehicle seats, etc.

Typically a headrest is supported by a rib or post extending downwardlyinto a seat or chair back in a positionable manner. Some headrests arepositionable, in an incremental fashion, to best support a user's head,the height of which will of course vary with different occupants. In achair used by several persons during a day, as for example a dentalchair, the headrest must be manually adjusted several times a day. Hencea headrest should be readily adjustable without substantial physicalforce being required For example, in a dental office the force requiredfor repeated adjustment during a working should not be excessive orexcessive to a dental assistant or the dentist. Further, a headrestshould not be susceptible to accidental displacement and yet infinitelyadjustable to support the user's head in an optimum manner.

SUMMARY OF THE PRESENT INVENTION

The present invention is directed toward the provision of a headrestassembly for use in place on chairs or vehicle seats and readilypositionable to accommodate a wide range of user sizes.

A guideway on the seat or chair houses a post for rectilinearpositioning. Infinite movement of the post is against the resistance ofa retainer assembly to the extent the headrest is not subject tounintentional displacement but yet readily positionable when desired. Aretainer member is biased into post engagement in a precise manner topermit such positioning with light or heavy forces as desired.

The retainer assembly is concealed within the chair back but yet readilyaccessible for retainer adjustment. Access to the retainer assembly isvia an opening in the chair back normally occupied by a removablefastener serving to secure a chair fitting. Added structure to a chairto provide such access to the interior of a chair back is therebyavoided as well as detracting from chair appearance. A retainer isbiased into contact with a post mounted sleeve of synthetic material toprovide post adjustment in a controlled manner.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a partial perspective view of a seat or chair back withfragments broken away to show the present invention;

FIG. 2 is an elevational view of the seat or chair back of FIG. 1 withthe present invention thereon;

FIG. 3 is a plan view taken along line 3-3 of FIG. 2;

FIG. 4 is a partial elevational view of FIG. 2 with a fastener removedfrom the chair back and a tool inserted for adjustment of the presentretainer assembly;

FIG. 5 is a perspective view of a retainer arm;

FIG. 6 is a bearing sleeve prior to forming for placement into a chairback mounted guideway or channel; and

FIG. 7 is a bottom view of FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the accompanying drawings wherein applied reference numerals indicateparts hereinafter identified, the reference numeral 1 indicatesgenerally a fragment of a chair back which may be the back of a dentalchair or that of another type of chair for example a vehicle seat. FIG.1 discloses an upholstery component 2. A reference numeral 3 indicatesthe chair back outer component which is of formed metal.

A channel 4 extends upwardly along the length of seat back 3 withchannel flanges 4A-4B secured to back 3 as by welds. Channel 4 and seatback 3 define an elongate open area or guideway 9 for the reception of apost 5 of a headrest assembly which includes a headrest proper at 6.Post 5 corresponds generally in section to the space defined by channel4 and the seat back to enable rectilinear positioning of post 5 tolocate headrest 6 a specific distance from the chair or seat bottom (notshown) to accommodate successive dental patients during a work day. Atthe upper terminus of channel 4 are tabs 7 each with a nut 8 securedthereto.

A retainer assembly located generally at 12 has a screw 16 with a headfor the reception of a tool for adjustment purposes as later described.A channel flange 20 carries a threaded element 21 for reception of screw16 the lower end of which bears upon an arm 22. An arm end 22A isdisplaceable relative a side 5A of post 5. A proximal end segment 23 ofarm 22 is moveably mounted on a flange 25 with a stud 24 on the armprojecting through an oversized opening 25A in flange 25. The somewhatelongate, oversized opening 25A permits limited arcuate movement ofretainer arm 22 in a plane containing post 5. Flange 4B defines anopening 19 to receive distal end 22A of arm 22.

A bearing sleeve at 26 is shown partially formed in FIG. 6 seats withinan upper end segment of channel 4 and provides for smooth, uninterruptedtravel of post 5. A segment 27 of the sleeve when installed in channel 4is intermediate retainer arm distal end 22A and post side 5A. Thebearing sleeve, best shown in FIGS. 6 and 7, is formed of a suitablesynthetic material such as polypropylene with fold grooves at 28enabling folding of the material into a shape of rectangular crosssection. When folded, an ear 29 of the sleeve extends outwardly from aside of the bearing for reception within a notched portion of channelflange 4A to fix sleeve bearing 26 within the channel. With attentionagain to bearing segment 27, flexibility of the segment is enhanced byslotting of the fold line at 30.

Per FIG. 3, a trim plate at 31 on the chair back defines an opening 32for passage of post 5. Trim plate fasteners at 33 and 34 engage tabs 7and nut elements 8. Adjustment of threaded member 16 to vary the actionof retainer arm 22 on post 5 would be infrequent and achieved uponremoval of fastener 34 leaving aligned openings in trim plate 31 and tab7, the nut 8 thereon to permit insertion of a tool 35 for engagementwith the upper end of adjustable member 16. Tool 35. as shown in FIG. 4,may have an hexagonal end for driving engagement with adjustable member16.

In some applications of the present headrest retainer, the headrest post5 may be virtually locked against any displacement.

While I have shown but one embodiment of the invention, it will beapparent to those skilled in the art that the invention may be embodiedstill otherwise without departing from the spirit and scope of theclaimed invention.

Having thus described the invention, what is desired to be secured by aLetters Patent is:

1. In a chair having back and a headrest assembly including a headrestand post, the improvement comprising, a guideway on the chair back inwhich the post is carried, a retainer assembly on the chair backincluding an arm having a distal end, adjustable means for biasing saiddistal end toward the post to inhibit post movement along the guidewayto enable headrest positioning relative the chair back by selecteddegrees of manual force.
 2. The improvement claimed in claim 1additionally including bearing of synthetic material interposed betweensaid distal end of the arm and the post of the headrest assembly.
 3. Theimprovement claimed in claim 1 wherein said arm has a proximal end, saidguideway having a support member supporting said proximal end of thearm.
 4. The improvement claimed in claim 1 wherein said adjustable meansincludes an adjustment screw.
 5. The improvement claimed in claim 4additionally including a cover plate on the chair back, a fastenernormally extending through an opening in said cover plate and into thechair back, said fastener in axial alignment with the adjustment screwand upon fastener removal permitting access to the adjustment screwthrough the cover plate opening for temporary application of a tool tothe adjustment screw to enable varying of the force applied to the postby said arm.
 6. In a chair having a back and a headrest assemblyincluding a headrest and a post, the improvement comprising, a guidewayon the chair back receiving the post, a retainer assembly including aretainer acting on the post, adjustable means for biasing the retainertowards the post to inhibit movement of the post along the guideway, anda removable fastener normally seated in the chair back and upon fastenerremoval providing an opening permitting access of a tool to saidadjustable means for altering the biasing force of said retainer appliedto the post.
 7. The improvement claimed in claim 6 wherein said retaineris an arm having a distal end proximate said post.
 8. The improvementclaimed in claim 7 additionally including a bearing of syntheticmaterial interposed between said distal end of the arm and the post ofthe headrest assembly.
 9. The improvement claimed in claim 6 whereinsaid guideway has a support member supporting the proximal end of thearm.
 10. The improvement claimed in claimed 6 wherein said adjustablemeans includes an adjustment screw.
 11. The improvement claimed in claim10 additionally including a cover plate on the chair back, a fastenernormally extending through an opening in said cover plate and into thechair back, said fastener normally in axial alignment with theadjustment screw and upon fastener removal permitting access to theadjustment screw through the opening for temporary application of a toolto the adjustment screw to enable altering the force applied to the postby said arm and hence post resistance to travel.
 12. An adjustableretainer for a headrest assembly supported by the back of a chair orvehicle seat and including, a guideway carried by the chair back, a postpositionable along the guideway to determine the elevation of a headrestcarried by the post, a retainer arm on the guideway proximate the postfor applying a force transversely of the post to inhibit post travelalong the guideway and a threaded member in abutment with the retainerarm and axially positionable to vary the force applied to the post andhence the degree to which post travel is inhibited
 13. The adjustableretainer for the headrest claimed in claim 12 additionally including abearing member of synthetic material interposed between the post and thedistal end of the retainer arm.